Did you try this route? I am looking at doing it coming back south .... I am going north through Springfield and then over the mountains ... staying in Bend for a few nights and then heading back south.

I have done Bend to Klamath Falls to Grass Valaley, and I have done Grass Valley to Klamath Falls to Crater Lake and on to Grants Pass including sight seeing at CL. Both times I stayed and charged at the KF KOA. They have a good 14-50 for electric cars, they have cabins and tent camping. Doing Bend to Grants Pass via Crater Lake should be OK but not much room for sightseeing.